Nacelle inlet assembly with acoustic panel

Abstract

An inlet assembly for a nacelle includes an inlet cowl and a plenum back wall of a fluid ice protection system (FIPS). The inlet cowl extends a length from a front end of the inlet cowl to a rear end of the inlet cowl. The inlet cowl includes a lipskin that defines a leading edge of the inlet cowl at the front end, and an acoustic panel coupled to the lipskin at an interface along an inner side of the inlet cowl. A seam is defined between the acoustic panel and the lipskin. The plenum back wall is affixed to an interior surface of the lipskin to define a plenum between the interior surface and a front surface of the plenum back wall. The plenum receives an anti-ice liquid. The plenum back wall is disposed in front of the seam along the length of the inlet cowl.

What is claimed is: 
     
         1 . An inlet assembly of a nacelle, the inlet assembly comprising:
 an inlet cowl that extends a length from a front end of the inlet cowl to a rear end of the inlet cowl, the inlet cowl including a lipskin that defines a leading edge of the inlet cowl at the front end, and an acoustic panel coupled to the lipskin along an inner side of the inlet cowl and defining a seam between a front end of the acoustic panel and the lipskin, wherein the acoustic panel is coupled to the lipskin via one or more fasteners that are spaced apart from an exterior surface of the lipskin and an exterior acoustic surface of the acoustic panel; and   a plenum back wall of a fluid ice protection system (FIPS), the plenum back wall affixed to an interior surface of the lipskin to define a plenum between the interior surface and a front surface of the plenum back wall, the plenum configured to receive an anti-ice liquid, wherein the plenum back wall is disposed in front of the seam along the length of the inlet cowl.   
     
     
         2 . The inlet assembly of  claim 1 , wherein the inlet cowl defines a cavity rearward of the leading edge between the inner side and an outer side of the inlet cowl, wherein the inlet assembly lacks a bulkhead within the cavity that fluidly isolates two portions of the cavity. 
     
     
         3 . The inlet assembly of  claim 1 , wherein the inlet cowl defines a cavity rearward of the leading edge between the inner side and an outer side of the inlet cowl, wherein the inlet assembly lacks thermal insulation elements within the cavity. 
     
     
         4 . The inlet assembly of  claim 1 , wherein the acoustic panel extends a length from the front end of the acoustic panel at the seam to a rear end of the acoustic panel at an inner aft edge of the inner side of the inlet cowl, wherein the length of the acoustic panel is at least 80% of the length of the inlet cowl from the leading edge to the inner aft edge. 
     
     
         5 . The inlet assembly of  claim 1 , wherein the acoustic panel includes a plurality of acoustic perforations to provide noise reduction. 
     
     
         6 . The inlet assembly of  claim 1 , wherein the seam between the lipskin and the acoustic panel is within 4 cm of the plenum back wall. 
     
     
         7 . The inlet assembly of  claim 1 , wherein the seam between the lipskin and the acoustic panel is within 6 cm of the leading edge of the inlet cowl. 
     
     
         8 . The inlet assembly of  claim 1 , wherein the lipskin defines perforations through the lipskin, the perforations located in front of the interface and align with the plenum to enable the anti-ice liquid to pass through the perforations onto the exterior surface of the lipskin. 
     
     
         9 . The inlet assembly of  claim 1 , wherein the lipskin includes a composite panel and a metallic coating disposed along an exterior surface of the composite panel to protect the composite panel from damage, the composite panel including a carbon fiber reinforced polymer (CFRP) material, and the metallic coating defining the leading edge of the inlet cowl. 
     
     
         10 . The inlet assembly of  claim 1 , wherein the lipskin includes titanium. 
     
     
         11 . The inlet assembly of  claim 1 , wherein the one or more fasteners include a first fastener that extends through the front end of the acoustic panel into a protrusion along the interior surface of the lipskin. 
     
     
         12 . The inlet assembly of  claim 1 , wherein the front end of the acoustic panel is bonded to the interior surface of the lipskin. 
     
     
         13 . The inlet assembly of  claim 1 , wherein the one or more fasteners include a pin that extends through the front end of the acoustic panel into a protrusion along the interior surface of the lipskin. 
     
     
         14 . A method of forming an inlet assembly of a nacelle, the method comprising:
 coupling an acoustic panel to a lipskin via one or more fasteners to define an inner side of an inlet cowl, the lipskin defining a leading edge of the inlet cowl, the inner side of the inlet cowl extending a length from the leading edge to a rear end of the acoustic panel, wherein a seam is defined between a front end of the acoustic panel and the lipskin, wherein the one or more fasteners are spaced apart from an exterior surface of the lipskin and an exterior acoustic surface of the acoustic panel; and   securing a plenum back wall of a fluid ice protection system (FIPS) to an interior surface of the lipskin to define a plenum between the interior surface and a front surface of the plenum back wall, the plenum configured to receive an anti-ice liquid, wherein the plenum back wall is secured at a location in front of the seam along the length of the inner side of the inlet cowl.   
     
     
         15 . The method of  claim 13 , wherein the one or more fasteners include a pin, and the acoustic panel is coupled to the lipskin via inserting the pin through the front end of the acoustic panel into a protrusion along the interior surface of the lipskin. 
     
     
         16 . The method of  claim 13 , the acoustic panel extends a length from the front end of the acoustic panel at the seam to the rear end of the acoustic panel, and the length of the acoustic panel is at least 80% of the length of the inner side of the inlet cowl. 
     
     
         17 . The method of  claim 13 , further comprising forming the lipskin to include a composite panel and a metallic coating disposed along an exterior surface of the composite panel to protect the composite panel, the composite panel including a carbon fiber reinforced polymer (CFRP) material, and the metallic coating defining the leading edge of the inlet cowl. 
     
     
         18 . The method of  claim 13 , wherein the acoustic panel is coupled to the lipskin and the plenum back wall is secured to the lipskin such that the seam between the lipskin and the acoustic panel is within 4 cm of the plenum back wall. 
     
     
         19 . The method of  claim 13 , wherein the acoustic panel is coupled to the lipskin such that the seam between the lipskin and the acoustic panel is within 6 cm of the leading edge of the inlet cowl. 
     
     
         20 . An inlet assembly of a nacelle, the inlet assembly comprising:
 an inlet cowl that includes an acoustic panel and a lipskin coupled together to define an inner side of an inlet cowl, the lipskin defining a leading edge of the inlet cowl, the inner side of the inlet cowl extending a length from the leading edge to a rear end of the acoustic panel, wherein a seam is defined between a front end of the acoustic panel and the lipskin, wherein one or more fasteners extend through the front end of the acoustic panel into a protrusion along an interior surface of the lipskin to couple the acoustic panel to the lipskin; and   a plenum back wall of a fluid ice protection system (FIPS), the plenum back wall affixed to the interior surface of the lipskin to define a plenum between the interior surface and a front surface of the plenum back wall, the plenum configured to receive an anti-ice liquid,   wherein the plenum back wall is disposed in front of the seam along the length of the inner side of the inlet cowl, and the seam is within 6 cm of the leading edge, and wherein a length of the acoustic panel from the front end to the rear end is at least 80% of the length of the inner side of the inlet cowl.